Field
The present disclosure relates to the design of an optical source. More specifically, the present disclosure relates to the design of an optical source that includes a combined distributed Bragg reflector (DBR) ring resonator in an optical cavity.
Related Art
Silicon photonics is a promising technology that can provide large communication bandwidth, low latency and low power consumption for inter-chip and intra-chip connections or optical links. In order to achieve low-latency, high-bandwidth optical connectivity, a variety of optical components are needed to implement high-speed, multi-wavelength silicon photonic links, including: optical modulators, optical detectors, wavelength multiplexers/demultiplexers and optical sources (such as silicon-assisted external-cavity lasers). These optical components often include a minor integrated into a silicon optical waveguide.
One approach for implementing an integrated minor is a distributed Bragg reflector (DBR). While DBRs can select a single wavelength, they have wide bandwidth, which typically makes DBRs a poor choice for long optical cavities because there would be numerous competing optical-cavity modes inside the DBR bandwidth.
Ring-resonator mirrors are often a better choice than DBRs for providing mode-selectivity because of their sharp resonance peaks. However, ring-resonator mirrors have periodic peaks that can occur multiple times within the spectral bandwidth of an optical gain medium, and thus can introduce competing optical modes in an optical source (such as a laser).
Hence, what is needed is a technique for implementing an integrated mirror without the above-described problems.